Purpose :
Exposure to airborne particulate matter can induce ocular surface damage and inflammation. We evaluated the effects of a topical mucin secretagogue on the protection of ocular surface damage induced by exposure to airborne black carbon, which is one of major airborne particulate matter components.

Methods :
Lewis Rats were exposed to ambient black carbon for two hours twice daily for five days. Corneal staining score and tear lactic dehydrogenase (LDH) activity were measured to evaluate ocular surface damage and compared with normal controls. Serum immunoglobulin (Ig) G and E were assayed using enzyme-linked immunosorbent assay, and the size of cervical lymph nodes was measured. The expression of interleukin (IL)-4, 17, and interferon (IFN)-γ in the anterior segment of the eyeball and cervical lymph nodes was measured by western blot analysis. Diquafosol tetrasodium was instilled six times a day from one day before exposure to five-day exposure duration and the ocular surface damages were evaluated and compared with saline instillation.